Self-clinching rivet



Feb. 22, 1938.. L. J. BAzzom SELF CLINCHING RIVET Filed June 5, 1936Patented Feb. 22, 1938 UNITED STATES SELF-OLINCHING RIVET Lewis J.Baz'zoni, Swampscott, Masa, assignor to United Shoe MachineryCorporation, Paterson, N. J., a corporation of New Jersey ApplicationJune 5, 1936, Serial No. 83,725

2 Claims.

This invention relates to self-clinching rivets. Such devices arebroadly very common and consist of an anvil or point deflecting memberand a separate nail or fastening member adapted to 5 cooperate with theanvil. The article is utilized by inserting the anvil in a previouslyprepared hole in the work and'then driving in the fastening member abovethe anvil, the point or points of the fastening member being deflectedwhen they strike the anvil.

While such devices, when properly made and used, may be mechanicallysuccessful, they are subject to the objection that each device consistsof two separate parts which have to be handied separately and correctlylocated, and that j g each part is useless if the other chances to get Imislaid.

It is an important object of the present invention to provide apractical one-piece article of the class discussed, in which'thefastening member and the anvil are formed from one piece of metal andare not separated from each other until the driving blow is given to setthem permanently in the work.

Accordingly I have provided a self-clinching rivet having a head, ashank and an anvil all integrally formed from one piece of stock, theshank being slotted to provide a plurality of tongues integral with theanvil at their outer ends which will be upset when the anvil is seatedat the bottom of a hole in the work and the head is struck a sharp blow.The tongues will preferably be tapered toward the anvil to facilitatesuch action.

5 In accordance with another feature of the invention I have provided agroove around the rivet at the junction of the shank and anvil member toreduce the thickness of the junction between the tongues and the anviland thus to provide frangible webs to facilitate the breaking of thetongues from the anvil under the driving blow. This groove isadvantageously formed in a v-shape, with one of the sides of the Vsloping inwardly and toward the head of the rivet, in order to deflectthe broken-off ends of the tongues outward.

. These and other features of the invention comprising certaincombinations and arrangements of parts will be apparent from thefollowing. description of a preferred embodiment of the invention shownin the drawings, in which Fig. 1 is a longitudinal cross-section of therivet looking in the direction of the planes of the clinching tongues;

(Cl. 8M0) Fig. 2 is a cross-section on the line II-II of Fig. l; and

Fig. 3 illustrates the application of the device to the attachment ofwood heels to shoes.

The rivet illustrated consists of a head in and 5 a shank l2 formed as atube by virtue of the bore M, the wall it of the shank it being of smallthickness relatively to its diameter. The integral anvil portion it isof the same outside diameter as the shank l2 and is separated from it byan annular groove 28 the lower face 2i of which is conical and slopesoutwardly and away from the head it at a considerable angle. The deepestpart of the groove Ed is preferably of somewhat smaller diameter thanthe bore it so that the inner face of the wall it overhangs the groove2% to a slight degree. The groove it does not, however, cut through thewall it, so that a thin web 22 connects the shank l2 and the anvil it.

The shank i2 is slotted from the groove 2b toward the head ill by aplurality of cuts. As illustrated, the slots 2 are two in number and areformed by two lateral cuts, as at 26, leaving only two tongues or legs28 from the wall it in this locality. The tongues 28 are shown asconsiderably narrower than the cuts 26, as tapering to 2 ward the anvilit, and are connected to the anvil by the thin webs 22 at their outerends.

The device is used as shown in Fig. 3, which illustrates the attachingof a wood heel to a shoe. A hole it is bored through the bottom 32 ofthe shoe 33 into the already located heel 3 3, which may be temporarilyheld in place by cement, the hole being an easy fit for the shank l2 andanvil it and of such depth as to leave the headill projecting for somedistance into the interior of the shoe when the anvil it is seated onthe bottom of the hole. Pressure or a sharp blow on the head it willbreak the webs 22, and the ends of the tongues 28 will slide down theconical surface 2E 40 and will thereby be forced to spread and curl intothe adjacent wood of the heel M. This fastens the heel so firmly inplace that it is impossible to pull it off Without destroying the heelor the shoe. If necessary, the head it] may be cut away by an end mill,and the heel then withdrawn.

The anvil i8 is illustrated as tubular, having a bore 36. This bore whenpresent should preferably be of smaller diameter than the bore it toprovide for suficient undercutting in the groove 20 and to stiffen theupper edge of the anvil member l8. This bore 36, when present, has theadvantage of reducing the weight of the rivet, and of permitting itslocation on a pin in the work, if desired.

The rivet of the present invention can be easily made, in quantity, uponan automatic screw machine.

Having described my invention, what I claim as new and desire to secureby Letters Patent 0! the United States is:

1. A self-clinching rivet comprising a tubular shank having a. head endand having at the end opposite thereto an integral extension to serve asan anvil, the wall of said shank having a plurality of circumferentiallyspaced openings extending from said anvil toward the" head end of theshank and which divide the shank' into a plurality of longitudinaltongues each of which at one end is joined to the anvil and all of whichY shank having a head end and having at the end opposite thereto anintegral cylindrical extension to serve as an anvil, the wall of saidshank being continuous at a locality adjacent to the head end and havinga plurali oi circumferentially spaced openings extendin rom saidcontinuous portion to said anvil, which openings are shaped to dividethe shank into a plurality of longitudinal tongues extending f m saidcontinuous portion of the shank wall to said anvil, each 01 said tonguesbeing joined to said anvil and each tapering from a relatively greaterwidth adjacent to said continuous portion 01 the shank wall to arelatively less width at its Junction with the anvil, said anvil at'

